A THEORETICAL INVESTIGATION OF THE $CH_{2}CN$ AMD $CH_{2}NC$ RADICALS
Loading...
Date
1994
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
The $CH_{2}CN$ and $CH_{2}NC$ radicals have been studied by the MR-$ACPF^{1}$ and CEPA-$1^{2}$ methods, using a basis set of 108 contracted Gaussian-type orbitals. Almost identical equilibrium geometries were obtained with both methods. The MR-ACPF results are: a) $CH_{2}CN: r_{e} (CH) = 1.079$ {\AA}, $\alpha_{e} (HCH) = 120.0^{\circ}, R_{1e} (CC) = 1.335$ {\AA}, and $R_{2e} (CN) = 1.175: b) \ CH_{2}NC r_{e} = 1,077$ {\AA}, $\alpha_{e} = 122,9^{\circ}, R_{1e} (CN) = 1.332$ {\AA}, and $R_{2e} (NC) = 1.204$ {\AA}. The wavenumbers of the $CH_{2}$ wagging mode of $CH_{2}CN$ is calculated to be $629 cm^{-1}$, (absoulte IR intensity: 51 km $mol^{-1}$) in good agreement with the recent high-resoultion study of Tanaka and $coworkers.^{3}$ The $CH_{2}$ rocking vibration ($\omega_{2}=1040 cm^{-1}$) is calculated to be about half as strong. The present calculations support the assignment of a peak observed at $1027 cm^{-1}$ in the argon matrix $spectrum^{4}$ to this vibration.
Description
$^{1}$ MR-ACPF: Multiconfiguration Reference Average Coupled Pair Functional; R. J. Gdanitz and R. Ahlrichs. Chem Phys. Lett. 143 413 (1998). $^{2}$ CEPA-1: Couple Electron pair Approximation; W. Moyer, J. Chem. Phys. 58, 1017 (1973) $^{3}$K. Tanaka, T. Harada, Y. Sumiyoshi, and T. Tanaka, contribution B-22 at the 22nd international Symposium at Free Radicals, Doorwerth, 1993. $^{4}$M. E. Jacox, Chem Phys. 43 157 (1979); private communication (1994).
Author Institution: Institut f\""{u}r Phsyikalische Chemie, der Universit\""{a}t G\""{o}ttingen
Author Institution: Institut f\""{u}r Phsyikalische Chemie, der Universit\""{a}t G\""{o}ttingen